RLG28 Retroreflective Sensors

TWINSBURG, Ohio, June 4, 2010 — Pepperl+Fuchs’ RLG28 retroreflective area sensors feature six light beams that generate a constant 60-mm detection field to consistently detect objects as small as 12 mm in diameter over the entire 0 to 4-m sensing range.

They are suitable for use in materials handling and other applications where single-beam retroreflective sensors have reached their functional limitations, or in applications that would otherwise require costly light grids. The sensors are cULus-listed.

They can detect leading edges of objects regardless of their shape, position or texture, and with no readjustment or realignment needed.

With some retroreflective sensors, shiny objects such as foils, Mylar and certain plastics can be erroneously “seen” as the sensor’s reflector. RLG28 sensors have a polarizing filter that eliminates the potential for such false readings. They automatically adjust excess gain based on ambient conditions such as lens contamination or temperature changes, enabling constant operation without requiring readjustment. They also offer enhanced status LED indication, better shock and vibration immunity per the international standard EN 60947-5-2, and low-end temperature rating to -30 °C for freezer/cooler environments.

They have mounting slots instead of holes, proprietary 4-in-1 output, brighter and larger light spots, and a single-step automatic teach all, making them faster to mount, wire and align. They feature a standard photoelectric sensor housing that is mechanically and electrically compatible with commonly available photoelectric sensors.

They are suitable for detecting the leading edges of pallets on palletizers and for identifying protruding pallets. They can be used in packaging, automotive and paper applications that require sensing objects with changing shapes or heights, such as pouches or bags; verifying the presence of objects with various textures, such as reflective chrome, glossy foil wrap, or soiled or damaged trays; verifying the presence of objects with variable positions, such as a stack of sheet metal bouncing as it moves on a conveyor; detecting objects with irregular or undefined edges, such as stacks of newspaper; detecting falling objects; and ejection control.

A filter that polarizes light passing through it. It is possible to fabricate sheets of plastic or gelatin that contain birefringent crystals so oriented as to pass only polarized light. Such sheets are more convenient to use than polarizing prisms.